GRM (Gauge readable movement) in Regin Premier gauges
To alleviate some confusion regarding the ‘grm’ of Regin Premier gauges using SG1.88 manometer fluid, the ‘grm’ of a water U-tube is the SAME as that of a Regin Premier manometer, because the arrangement is a ‘J’ gauge style with almost all of the fluid movement in the indicating column.
When a U-tube gauge is pressurised, the fluid rises in one column and falls the same distance in the other. In a ‘J-tube’ gauge however, almost all the fluid movement is in the indicating column, with a small height change in the reservoir section. This means that for a given pressure change in one column, the fluid movement of a High Specific Gravity ‘J’gauge is virtually the same as the movement of water in one column of a U-Tube type gauge.
The statement that the grm of a gauge is dependant only on the SG of the indicating fluid is erroneous for the reasons stated above. This is why the IGEM UPE 1B was altered to allow for higher specific gravity fluids.
In summary, a Regin Premier gauge is suitable for use wherever a water filled U-gauge is suited to the application.
